Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 5dcc942..dd2cdc0 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -1,20 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Based on arch/arm/kernel/signal.c
  *
  * Copyright (C) 1995-2009 Russell King
  * Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <linux/cache.h>
@@ -296,11 +285,6 @@
 	 */
 
 	fpsimd_flush_task_state(current);
-	barrier();
-	/* From now, fpsimd_thread_switch() won't clear TIF_FOREIGN_FPSTATE */
-
-	set_thread_flag(TIF_FOREIGN_FPSTATE);
-	barrier();
 	/* From now, fpsimd_thread_switch() won't touch thread.sve_state */
 
 	sve_alloc(current);
@@ -470,7 +454,7 @@
 			offset = 0;
 			limit = extra_size;
 
-			if (!access_ok(VERIFY_READ, base, limit))
+			if (!access_ok(base, limit))
 				goto invalid;
 
 			continue;
@@ -556,7 +540,7 @@
 
 	frame = (struct rt_sigframe __user *)regs->sp;
 
-	if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+	if (!access_ok(frame, sizeof (*frame)))
 		goto badframe;
 
 	if (restore_sigframe(regs, frame))
@@ -730,7 +714,7 @@
 	/*
 	 * Check that we can actually write to the signal frame.
 	 */
-	if (!access_ok(VERIFY_WRITE, user->sigframe, sp_top - sp))
+	if (!access_ok(user->sigframe, sp_top - sp))
 		return -EFAULT;
 
 	return 0;